This application claims benefit of Japanese Patent Application No. 2000-139468 filed on May 12, 2000, the contents of which are incorporated by the reference.
The present invention relates to conveying interval adjusting method and apparatus or to conveying interval adjusting method and apparatus in the conveying of postal matter and like conveyed matter on belt conveyer at a predetermined interval.
In the prior art, conveyers for conveying (or moving) thin postal matter such as postal letter envelops and postal cards from one place to another for such purposes as sorting of postal matter and recognition of postal numbers, are disclosed in, for instance, Japanese Patent Laid-Open No. 6-206647 entitled xe2x80x9cConveyerxe2x80x9d, Japanese Patent Laid-Open No. 11-19595 entitled xe2x80x9cPostal Matter Internal Adjuster, Postal Matter Interval Adjusting Method and Postal Matter Sorter/Accumulatorxe2x80x9d and Japanese Patent Laid-Open No. 11-290787 entitled xe2x80x9cPaper Sheet Conveyorxe2x80x9d.
FIG. 7 is a side view showing a typical prior art example of such postal matter conveyer. In this conveyer, postal matter (or conveyed matter) 3 is clamped between a pinch roller (which is not movable) 1 and a pinch roller unit (which is movable) 2. The movable pinch roller unit 2 includes a pair of rollers 2a and 2b and an endless belt 2c passed thereon. The conveying interval of the postal matter 3 is determined by adjusting the rotation number of the pinch roller 1 and the pinch roller unit 2.
The above prior art conveying interval adjusting system has the following problems. A first problem is posed by the pinching of the conveyed matter with the pinch rollers. More specifically, with different thicknesses of conveyed matter as the subject of processing, the pinch rollers offer resistance to the conveyed matter, thus leading to troubles in the conveying interval adjustment. Secondly, because of the pinching of the conveyed matter with the pinch rollers, the processing of conveyed matter which is readily subjected to damage is impossible. In this case, it is necessary to sort out the conveyed matter before the conveying thereof.
An object of the present invention is to provide conveying interval adjusting method and apparatus, which permit adjusting the conveying interval of conveyed matter independently of the thickness and contents of the conveyed matter.
A conveying interval adjusting apparatus according to the present invention comprises a bottom belt movable at a predetermined speed in the direction of conveying conveyed matter, and a belt disposed perpendicularly to the bottom belt, the perpendicular belt having profile members for accelerating or decelerating the conveyed matter conveyed on the bottom belt, thereby adjusting the conveying interval of the conveyed matter. The bottom belt is inclined by 15 degrees to 45 degrees relative to horizontal place with the conveying direction as axis, and thus forms a valley-like conveying path in cooperation with the belt surface of the profile belt. In the preferable embodiment, the two belts with the profile members are each driven by a pair of pulleys which are coaxial (in same axis) with pair pulleys, respectively, for driving the other. The pair pulleys are coupled by synchro-belts to drive motors, respectively. The two belts with the profile members each have a pair of profile members symmetric with each other. Each belt with profile members has two pairs of profile members a pair of profile members for acceleration and the other for deceleration. The profile member for acceleration has a reinforcing member mounted on one side, and the profile member for deceleration has a reinforcing member mounted on the other side.
According to a conveying interval adjusting method for adjusting the conveying interval of conveyed matter by disposing a belt with profile members to be perpendicular to a bottom belt driven at a predetermined speed in the direction of conveying the conveyed matter, and accelerating or decelerating the conveyed matter by causing the profiles of the belt with profile members to be in contact with leading or trailing end of the conveyed matter. In the preferred embodiment, two belts with profile members are provided and driven independently for accelerating or decelerating the conveyed matter.
Other objects and features will be clarified from the following description with reference to attached drawings.